Electroluminescence is the emission of a light from a luminescent material when an electrical field of proper value is applied to the material. This property has been utilized in the prior art to construct display panels. The first wave of devices were of the AC type which used the luminescent material as the dielectric in a parallel plate capacitor where one of the parallel plates was transparent. When an alternating voltage was applied to the parallel plates the luminescent material emitted light. By depositing rows of conductive material on one surface of the luminescent material and columns of conductive material on the opposite surface, an X-Y matrix is formed. At each crossover point of a column and a row a pixel for a video display is formed. With the proper excitation at the crossover points the pixel positioned at that point will emit light. Drive circuits are then coupled to the rows and the columns to vary the level of current or voltage that is applied as a function of the amount of light that is to be generated by each pixel.
Advances in the electroluminescent material art have led to organic materials being used in such type displays which materials provide high brightness levels, and low DC voltage requirements along with multicolors. In addition, recent developments have resulted in display panels with a high density of addressable pixels. With such displays, it is desirable to be able to store imaging data so that the display can be operated without external memory and without continual refreshing. In addition, it would be advantageous to be able to control the brightness of the display with binary signals rather than analog signals thereby permitting the display to be driven by a computer.